Russian opposition leader Alexei Navalny has been added to an official list of "terrorists and extremists" by Moscow.

Navalny -- who has been imprisoned for more than a year -- was included in the latest registry alongside some of his allies on Tuesday.

The decision by Russia's Federal Financial Monitoring Service means his bank accounts will be frozen under Russian law. The Taliban and the so-called Islamic State are among those on the list.

It is the latest move in a months-long crackdown on Russia's opposition, as well as independent media and human rights activists.

Eight of Navalny's top aides — including Georgy Alburov and exiled Lyubov Sobol — were also added to the registry. Two other allies of the Kremlin critic had already been added to the list earlier this month.